At the time S. chenii was described it was known from only two specimens, but additional specimens have since been discovered. This species is distinct from all other Syrrhopodon species, except S. hongkongensis, by its remarkable intramarginal rows of spinose papillae on the leaves, with the leaf cells otherwise smooth abaxially. Although S. chenii may be superficially similar to S. spiculosus, that species has its leaf cells strongly abaxially papillose, among other differences. In some specimens of S. chenii the leaves are mostly broad; in other specimens, such as P.-J. Lin 4413 (IBSC, LAF), many leaves are very narrow and quite different in aspect from the broad leaves. See comments under the very similar S. hongkongensis for differentiation from that species.